IC 443, Jellyfish Nebula, a supernova remnant in the constellation Gemini, at an approx distance of 5,000 light years. The supernova possibly occurred between 3,000 and 30,000 years ago.
The bright star at the bottom is Eta Geminorum.
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Technical info:
TS 80mm f6 APO triplet refractor
ZWO ASI 071 MC PRO - temp: -5c - gain 0
TS 0,79 reducer
Optolong L-eNhance dualband filter ( Ha-OIII)
iOPTRON CEM25P mount
ASIAIR Pro
Exposure - 132x 300sec - ~ 11 hours
Processed with Astro Pixel Processor - PS CS5